Chain conveyors are suitable for transporting heavy workpieces and have the advantage that the chain can continue to run when workpieces or workpiece carriers are stopped. In so doing, rollers roll at the supporting surface of the workpiece or workpiece carrier so that only rolling friction occurs during the relative movement of the parts, and only a relatively limited drive power is necessary for the continued movement of the chain. It is disadvantageous in such chain conveyors that chips, screws and similar small parts, which, when the workpiece is stopped but the chain continues to run, can damage the supporting surface of the workpiece or of the workpiece carrier and fall into the wedgelike frame spaces in the chain which are formed between the rollers.